Kerf cutter



Jan. 9, 1951 W, C, CASSELL 2,537,331

KERF CUTTER a f 1 U v INVENTOR.

W. C. CASSELL Jan. 9, 1951 KERF' CUTTER Filed March 2l. 1947 INVENTOR.@d Je Patented Jan. 9, 1951 UNITED ASTATES PATENTv OFFICE KERF CUTTERWilliam C.. Cassell, Williamson, W. Va. Application March 21, 1947,serialNo. i736,335 2, Claims. (Cl. 2642-30) My invention relates to animprovement in mining machinery, particularly to aA means and method forcontrolling the `front end of a cutter bar.

It is a'principal object of my invention to provide a means andmethodfor controlling the upward and downward movement of the front endof the cutter kbar of acoal cutting machine while saidend is inserted inthe cut made in a coal pocket.

1t is an important object of my invention to combine hydraulic jackswith the cutter bar of a standard coal cutting machine in such mannerthat the said cutter bar may be adjusted to cutl nearer the bottom` ofthe coal pocket than is possible in any known coal-cutting machine, andto raise the said cutter bar if Srock Vis encountered.

It is a further objectof my invention to provide such means andmethod`which is quickly adjustable to any desired cutting position so that thehorizontal kerfs cut in the coal face will be neither too far from therock bottom or too high in the coal bank.

It is a still further object to provide such means and method as willpermit such control as to cut out a larger percentage of impurities withless coal waste.

It is another object to provide such means as will be simple andefficient in its operation, and which will greatly reduce wear and tearon the cutting bits since rock ledges may be avoided.

Other objects and advantages of the invention will become apparentduring the course of the following specification and accompanyingdrawings, forming part of the specication, wherein like numerals areused to designate like parts throughout.

In the drawings:

Figure 1 is a side elevation of a kerf cutter embodying my inventionwith the cutter bar inserted in a kerf cut in a coal pocket, andillustrating the application of my fluid system on the machine.

Figure 2 is a vertical section through the up jack cylinder,

Figure 3 is a transverse section through the same, taken substantiallyon the line 3-3 of Figure 2, and

Figure 4 is a diagrammatic View of the uid system, a fragment of thefront end of the cutter bar and a few of the kerf cutting bits beingshown.

Referring now in detail numeral I refers generally to a standard kerfcutting machine of the bottom cut type, pro-.-

to the drawings, the

vided with the usual' meansfor controlling the outwardly extendingcutter bar Il mounted on the said machine for pivotal up and downmovement, A plurality of cutting bits I2'are mounted on an endless chain(not shown) andadapted to rotate about the margin of the said cutter barto cut the lhorizontal kerfin the coal pocket. Since the machine I0 iswell known in the art, and forms no part' of'my invention other thanwill be hereinafter described, no further descrip.- tion-need be given.

Referringnow to the fluid system of'my'invention, the numeral I3designates a fluid compression tank containing a fluid, preferably oil,supported on the body of the machine I0. The tank is provided with aninternal reciprocal piston I4 adapted to pump vthe fluid under pressureby means of a pivoted handle lthrough suitable-ports into a conduitlleading to a pair'of standard manually operated rotary valves Il andI8, each said valve having a control handle IS and 20, respectively. Thesaid tank I3 is also provided with means to receive iiuid from a returnconduit 2|. Since any standard compression tank and three way valve maybe used, these elements are not further described.

The numeral 22 designates a spring-loaded cylindrical hydraulic jacksuitably mounted in the cutter bar l I adiacent the front end thereof.It comprises a uid-tight cylinder comprising a bottom portion 23 havinga port 24 through which fluid under pressure may be received by means ofa conduit 25 connected to the source of uid through the valve Il and athreadedly connected top portion 2B provided with an integrally formeddependent annular flange 21 arranged for up and down transverse slidingmovement along the inner periphery of bottom portion 23 providing a stopfor the heads 28 of a piston 29 adapted to reciprocate within saidcylinder under pressure of the fluid supplied through the conduit 25under control of the valve ll, the thrust of the said piston 29 beingadjustable for a desired amount of raising by means of the threadedconnection 3l) between the bottom portion 23 and the top portion 2,6. Ahelical compression spring 3| is suitably connected to the bottom of thelower portion 23, as at 32, and at the top of an apertured recess 33 inthe piston 29 and head 28, as at 34, to return the said piston to itsnormal position quickly upon reduction of the pressure within the saidcylinder, the said spring tensioning with the upward movement of thepiston 29. The said jCk, Will force the cutter bar downwardif cuttingtoo high in the coal pocket by pressure of the piston 29 against the topof the kerf when fluid is admitted into the cylinder through themanually controlled valve I'I.

The numeral 35 designates a jack of identical construction with the jack22, except that the spring 3| and its connections to the bottom of thecylinder and within an aperture are omitted. Since the piston 36 ofvalve 35 depends downward to impinge upon the bottom of the kerf, such aspring is not needed. The said piston being pushed back into thecylinder 31 by the pressure of the bottom of the kerf when inside fluidpressure is relieved. The jack 35 is supplied with hydraulic fluidthrough the conduit 38 and said pressure is controlled by the valve I8.

It is to be understood that the jacks 22 and 35 are mounted in thecutter bar II so that the outer surfaces of the respective pistons 29and 36 are normally substantially level with the respective top andbottom surfaces of the said bar to provide no obstruction to the normaluse of the bar.

While I have described my invention in connection with a bottom cuttingtype of kerf machine, it is to be understood that it may also be usedwith a track or mobile kerf cutter. It is to be further understood thatvarious changes in the shape and arrangement of the parts, orsubstitution of materials and equivalents may be made without departingfrom the spirit of the invention within the scope of the subjoinedclaims.

The operation of my fluid system is very simple. 'If the machine iscutting in rock, by operating the compressor tank I3 iiuid underpressure is forced into the jack 35 and the front end of the cutter Ilis forced upward. If the cut is too high, fluid is forced into the jack22 and the 4 cutter is forced downward. Control is maintained throughthe respective valves I8 and I1. Relieving the pressure in therespective jacks causes the jacks to return to their normal positions asheretofore described.

Having thus disclosed my invention, I claim:

1. A kerf cutting machine comprising a frame adapted to slide along itsbottom wall and a relatively narrow cutter bar extending from the frameand rigidly connected thereto, an endless cutter chain carried by thecutter bar, a source of fluid pressure mounted on the frame, means forcontrolling the direction of iiow of the fluid pressure, hydraulic jacksconnected to the source of fluid pressure and mounted within the cutterbar adjacent the free end thereof and in alignment with the longitudinalaxis of the cutter bar, the jacks being extendable in oppositedirections to depress and raise the free end of the cutter bar whenactuated by the uid pressure.

2. A kerf cutting machine as set forth in claim 1, wherein a portion ofthe cylinder is adjustable to vary the throw of the jack and the amountof vertical movement of the cutter bar.

WILLIAM C. CASSELL.

REFERENCES CITED The following references are of record in the file ofthis Ipatent:

UNITED STATES PATENTS Number

